Wider tires = worse handling? +Alignment? +PSI?

[mualan]

Hi all,

I've done some searches already, but couldn't find an answer so if this info is already on this forum somewhere, just let me know.

I recently got a new set of Sumitomo HTRZ II's (205-50-16) to replace my stock Dunlops (195-50-16). The tires are only a few days old, but I'm noticing that the turning radius of the car is a little wider than it used to be. I'm guessing that it's due to the wider tires, but is this right?

My second concern is how everyone says that when replacing a 4 tires, alignment should get checked. My P5 is going on 1.5 years, 30,000 miles. I haven't had any perceived alignment issues so far, so I'm wondering just how important it is that I get this done?

And finally, I kept the stock Dunlops at the recommended 32 psi. Should it be any different for different tires (namely my new Sumitomo's)?

Thanks in advance for the help.

-mualan
stock Laser-Blue P5 except for
- K&N air filter
- Sumitomo HTRZ II tires (205-50-16)
- dog hair on the leather

 

[Sir Nuke]

the turning radius of the car must be a PERCEPTION since you didn't change anything other than your tires....the only thing that could change your turning radius is if you aren't turning the wheels as far....and if you are turning the steering wheel to the lock and the tires aren't rubbing...the radius is the same.

the presure is most likely just fine...there won't be that much difference...

as for the alignment....if you were not experiencing any odd or bad wear patterns on your Dunlops before you changed tires....you do NOT need an alignment...you would just be wasting your money.

BTW...welcome to the club! (stash)

 

[BadApple]

i have 205/50/16's and my car sticks to the concrete...nothing has changed...i havnt had a tire alignment since i put the, on and everything is great. firestone told me that as long as the car was not allready having alignment problems that the tires would not make any difference.
a wider tire will not effect the turning radius.
Welcome !
-NOX

 

[Douggie]

Well, I'd have to say it depends on how you think about it.

When you turn the wheel (till lock), the wheel will need some time to go from the straight position to the full locked position. Assuming the power steering always gives a constant force to turn the wheels, with an increased contact area (wider tires), there will be more friction or resistance working against the power steering. This leads to an increased time taken for the WHEELS to do the full lock (yes, your steering column may have locked, but the wheels may still lag behind if there is sufficent resistance). Needless to say, this will affect the turning radius. Of course it also depends on your speed when doing the turn.

And this is of course my BS theory based on physics. But then again because we're talking about a 10mm difference in width, so it should not make a noticable difference.

Therefore, it must be a PERCEPTION

 

[mualan]

Thanks for the great knowledge everyone. I think I'll go ahead and not get an alignment until I really need one. (you guys just saved me some money!)

As for the turning radius, both my girlfriend and I notice a change. My guess right now is that since the tires are so new and possibly more grippy/sticky than my old ones, there may be a little more resistance when turning the steering wheel. At any rate, I noticed a huge change in how the car turned when going in reverse ... backing into parking spots used to be like second nature to me. I dunno, it just handled differently.

In all though, I'm happy with my new tires.

Thanks for the welcome. I'm glad to be here.

mualan

 

[Douggie]

Thanks for the great knowledge everyone. I think I'll go ahead and not get an alignment until I really need one. (you guys just saved me some money!)

As for the turning radius, both my girlfriend and I notice a change. My guess right now is that since the tires are so new and possibly more grippy/sticky than my old ones, there may be a little more resistance when turning the steering wheel. At any rate, I noticed a huge change in how the car turned when going in reverse ... backing into parking spots used to be like second nature to me. I dunno, it just handled differently.

In all though, I'm happy with my new tires.

Thanks for the welcome. I'm glad to be here.

mualan

Both of you having wrong perceptions??? Then it might help if both of you stop smoking whatever you smoke while driving (smoke) just kidding, LOL.

But maybe you should increase your tire pressure a little. I ran my Dumblops at 35 psi and I like how it feels/handles. I'm still not sure how they determine the recommended psi for the stock tires but it's common sense that if you use a different tire size, their recommended psi may not be optimal anymore.

Try getting it up to 35 psi and report back here ASAP.